The invention pertains to an integrated digital gain control circuit for digital chrominance signal in digital color television receivers.
One integrated digital gain control circuit is disclosed in EP-OS No. 00 95 543. With the aid of this circuit, the burst amplitude on the back porch of the composite color signal is compared with an internally stored reference value and brought to the desired amplitude value with the aid of a multiplier having an adjustable multiplication factor. In this way, the color saturation is normalized during the image reproduction at the receiving end, so that amplitude interferences along the transmission path, such as may be caused by reflections, by weak incoming receiving signals or by a television receiver inaccurately adjusted to the receiving frequency only have small effects within certain limits. Operation of this gain control circuit has shown, however, that the originally provided control range is too small. It would be desirable to have the gain control range enlarged so that very weak color signals can be applied to the color stage for further processing with a satisfying color reproduction.